package com.fhz.netty.server.websocket.handler;

import com.fhz.netty.server.websocket.utils.ChannelSupervise;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.*;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.HttpVersion;
import io.netty.handler.codec.http.websocketx.*;
import io.netty.util.CharsetUtil;
import lombok.extern.slf4j.Slf4j;

import java.util.Date;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import static io.netty.handler.codec.http.HttpUtil.isKeepAlive;

@Slf4j
public class ScctChannelHandler extends SimpleChannelInboundHandler<Object> {

    private WebSocketServerHandshaker handshaker;


    @Override
    protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
        log.debug("收到消息："+msg);
        if (msg instanceof FullHttpRequest){
            //以http请求形式接入，但是走的是websocket
            handleHttpRequest(ctx, (FullHttpRequest) msg);
        }else if (msg instanceof WebSocketFrame){
            //处理websocket客户端的消息
            handlerWebSocketFrame(ctx, (WebSocketFrame) msg);
        }
    }



    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        //添加连接

        String userId = ctx.attr(ChannelSupervise.ATTRIBUTE_KEY_USER_ID).get();
        log.debug("客户端加入连接:{},userid={}",ctx.channel(),userId);
        ChannelSupervise.addChannel(ctx.channel(),userId);
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        //断开连接
        log.debug("客户端断开连接："+ctx.channel());
        ChannelSupervise.removeChannel(ctx.channel());
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
    }

    private void handlerWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame frame){
        // 判断是否关闭链路的指令
        if (frame instanceof CloseWebSocketFrame) {
            handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain());
            return;
        }
        // 判断是否ping消息
        if (frame instanceof PingWebSocketFrame) {
            ctx.channel().write(
                    new PongWebSocketFrame(frame.content().retain()));
            return;
        }
        // 本例程仅支持文本消息，不支持二进制消息
        if (!(frame instanceof TextWebSocketFrame)) {
            log.debug("本例程仅支持文本消息，不支持二进制消息");
            throw new UnsupportedOperationException(String.format(
                    "%s frame types not supported", frame.getClass().getName()));
        }
        // 返回应答消息
        String request = ((TextWebSocketFrame) frame).text();
        log.debug("服务端收到：" + request);
        TextWebSocketFrame tws = new TextWebSocketFrame(new Date().toString()
                + ctx.channel().id() + "：" + request);
        // 群发
        log.info("发送消息");
        ChannelSupervise.send2All(tws);
        // 返回【谁发的发给谁】
        // ctx.channel().writeAndFlush(tws);
    }

    /**
     * 唯一的一次http请求，用于创建websocket
     * */
    private void handleHttpRequest(ChannelHandlerContext ctx,
                                   FullHttpRequest req) {
        //要求Upgrade为websocket，过滤掉get/Post
        if (!req.decoderResult().isSuccess()
                || (!"websocket".equals(req.headers().get("Upgrade")))) {
            //若不是websocket方式，则创建BAD_REQUEST的req，返回给客户端
            sendHttpResponse(ctx, req, new DefaultFullHttpResponse(
                    HttpVersion.HTTP_1_1, HttpResponseStatus.BAD_REQUEST));
            return;
        }


        String uri = req.uri();

        ConcurrentMap<String, String> paramMap = getUrlParams(uri);
        log.debug("获取uri中参数={}",paramMap);
        if (paramMap.get(ChannelSupervise.KEY_USER_ID)==null){
            sendHttpResponse(ctx, req, new DefaultFullHttpResponse(
                    HttpVersion.HTTP_1_1, HttpResponseStatus.BAD_REQUEST));
            return;
        }

        WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(
                "ws://localhost:8081/websocket", null, false);
        handshaker = wsFactory.newHandshaker(req);
        if (handshaker == null) {
            WebSocketServerHandshakerFactory
                    .sendUnsupportedVersionResponse(ctx.channel());
        } else {
            handshaker.handshake(ctx.channel(), req);
            ChannelSupervise.setChannelParam(ctx.channel(),paramMap.get(ChannelSupervise.KEY_USER_ID));
        }



    }
    /**
     * 拒绝不合法的请求，并返回错误信息
     * */
    private static void sendHttpResponse(ChannelHandlerContext ctx,
                                         FullHttpRequest req, DefaultFullHttpResponse res) {
        // 返回应答给客户端
        if (res.status().code() != 200) {
            ByteBuf buf = Unpooled.copiedBuffer(res.status().toString(),
                    CharsetUtil.UTF_8);
            res.content().writeBytes(buf);
            buf.release();
        }
        ChannelFuture f = ctx.channel().writeAndFlush(res);
        // 如果是非Keep-Alive，关闭连接
        if (!isKeepAlive(req) || res.status().code() != 200) {
            f.addListener(ChannelFutureListener.CLOSE);
        }
    }


    /**
     * 连接关闭
     *
     * @param channelHandlerContext
     */
//    @Override
//    public void handlerRemoved(ChannelHandlerContext channelHandlerContext) {
//        channelGroupUtil.userRemove(channelHandlerContext.channel());
//    }

    /**
     * 异常处理
     *
     * @param channelHandlerContext
     * @param cause
     */
//    @Override
//    public void exceptionCaught(ChannelHandlerContext channelHandlerContext, Throwable cause) {
//        channelGroupUtil.userRemove(channelHandlerContext.channel());
//    }

    /**
     * 心跳检查处理 HEART_CHECK
     *
     * @param channel
     */
    protected void heartCheckHandler(Channel channel) {
        log.info("心跳检测");
//        messageSender.sendMessage(channel, WebSocketDTO.data(ModuleEnum.HEART_CHECK, "回复心跳检查"));
    }

    private static ConcurrentMap<String, String> getUrlParams(String url) {
        ConcurrentMap<String, String> map = new ConcurrentHashMap<>();
        url = url.replace("?", ";");
        if (!url.contains(";")) {
            return map;
        }
        if (url.split(";").length > 0) {
            String[] arr = url.split(";")[1].split("&");
            for (String s : arr) {
                String key = s.split("=")[0];
                String value = s.split("=")[1];
                map.put(key, value);
            }
            return map;

        } else {
            return map;
        }
    }

//    /**
//     * 注册用户 USER_REGISTER
//     *
//     * @param channel
//     */
//    protected void registerHandler(Channel channel) {
////        UserRegisterDataDTO userRegisterDataDTO = JSON.parseObject(JSON.toJSONString(request.getData()), UserRegisterDataDTO.class);
////        String userId = userRegisterDataDTO.getUserName() + "_" + webSocketEnum.name() + "_" + userRegisterDataDTO.getDevice().name();
//        String userId = channelGroupUtil.getUserIdByChannel(channel);
//        //关闭 userId 的其他channel
//        channelGroupUtil.removeChannel(userId);
//        //将该 channel绑定userId，存入UserChannelMap
//        channelGroupUtil.userRegister(channel, userId);
////        messageSender.sendMessage(channel,
////                WebSocketDTO.data(ModuleEnum.USER_REGISTER, userId + "用户已注册"));
//    }



//    /**
//     * 注册用户 USER_REGISTER
//     *
//     * @param channel
//     * @param request
//     * @param webSocketEnum
//     */
//    protected void registerHandler(Channel channel, WebSocketDTO request, WebSocketEnum webSocketEnum) {
////        UserRegisterDataDTO userRegisterDataDTO = JSON.parseObject(JSON.toJSONString(request.getData()), UserRegisterDataDTO.class);
//        String userId = userRegisterDataDTO.getUserName() + "_" + webSocketEnum.name() + "_" + userRegisterDataDTO.getDevice().name();
//        //关闭 userId 的其他channel
//        channelGroupUtil.removeChannel(userId);
//        //将该 channel绑定userId，存入UserChannelMap
//        channelGroupUtil.userRegister(channel, userId);
//        messageSender.sendMessage(channel,
//                WebSocketDTO.data(ModuleEnum.USER_REGISTER, userId + "用户已注册"));
//    }
}
